Internal-combustion engine



' 3%; ingthe a Patented Aug. '17; 1926.

UNITE-D STATES I 1,596,401 PATENT OFFICE,

EVERETT B. BURTNETT, LOS ANGELES, CALIFORNIA, ASSIGNOR, BY DIRECT ANDMESNE'ASSIGNMENTS, TO THE AUTOMOTIVE VALVES CO., OF EOS ANGELES, CALI-FORNIA, A VOLUNTARY rnus'r;

'7 INTERNAL-COM BUSTIQN ENGINE.

- Application filed :rul ic, 1924, seriarno. 726,323.

My invention relates generally .to inte r* described are disposed a rowwith their 55 nal combustion engines, and more particularly to enginesof the two stroke. cycle type, the principal object of my inventionbeing to provide a multi-cylinder, engine madeup of a plurality ofunits,'each unit comprlsmg a gaseous fuel pumping cylinderthatjseffective in precompressingi gaseous fuel and forcing the same intoapair of combustion H chambers, and which latter are connected at theirhead orinner ends by "a clearance chamber that is common to both of saidcombustion chambers. I 3

Further objects of my 'invention' a're to generally improve upon andsimplify the construction of multi-cylinderjtwo stroke cycle internalcombustion engines, to provide an'improved crank shaft arrangementwherein the cranks for the-pistons in the cylindersj'of thevarious'units are arranged in relation to each other so; as toiminimiz'ecentrifugal couple and tor'otateunder all speeds with minimumvibrationand with greatest advantage in power output.

\Vith'the foregoing and other 0 view, my invention consists in thefeatures of construction and combination.and ar-v rangeiiient of "partshereinafter more fully' described and claimed, reference being-had totheae nipanyingdrawings, in which Figure-f1 is "avertical' section takenlength wisethroughthe center of an engine em bodyin'g] the principles ofinvention;

Figure 2 is a diagrammatic view illustratrr angement of'cranks in thecrank shaftof; my improved engine.

Referring b l n'umerals to the accompanying drawinga wliich illustrate apract cal flembodimentofmy invention, 10 design-ates ac linder" blockthe walls of which are pref "erahlyfiormed with' communicatingchambersilfl, through which maybe circulated -a .fluid..:fcoolingmedium, "and formed-in said block isuitably spaced apart are ,threegaseou .fuelprecompres'sion and pumping chambers;12,?13"and 14:. Y H 1For 'LedPin"the*:block 10and immediately adjacentjw to chamber 12'- :are combustion chambers 15 and r l'6, {and a Similar pair of cbmbustionchambers rll'fand lame formedin the block adjacent to. pumping chamber13. Ajthirdpair' combustion chambers 19 and 20 are-formedin thejblock,adjacent to pumping chamber 14'. The chiimbersjust bie'sts axes paralleland occupying the same radial plane with respect to the axis of thecrank shaft. Thus each pumping chamber is ar- "ranged between a pair ofcombustion cham bers, andeach set of three. chambers con stitutes apower unit for the engine.

Suitably secured on the head end of the cylinder block 10 is a headblock 21 in the under side of which are formed three chambers 22,23 and24:. The ends of chamber 22 communicate directly with combus' tionchambers 15 and 16,'thereby providing a conimon clearance compressionand combustion chamber. In a similar manner, chamber 23 connects thehead or inner ends of the combustionchambers 17 and 18, and chamber 24;connects the head or inner ends "of the combustion chambers 19 and 20.

Seated inthe .upper portion of head 21 and preferably at points abovethe chambers '16, 18 and 20 are spark plugs 25, the terminals of theelectrodes of which pro 'ject, respectively, into the common clearancechambers 22, 23 and 24. Cylinder block -10 snrmounts a crank case member26, the *same being provided with four or more properly ,spaced'bearings 27 1501 a crank Shaft 28,." which latter is provided with ninecranks or throws, one for each engi'ne cyl- -,inder."

Apiston 29 that is arranged for operatibn pumping chamber 12 isconnected by a connecting rod 30 to a crank '31 on shaft 28, said crankbeing disposed between and arranged diametrically opposite to, or 180from, cranks '32 that are located beneath the combustion chambers 15 and16. Connecting =ro$ls 33%:onnect the cranks 32 with pistons 3d that arearranged for operation within combustion chambers 15 and 16; A pumpingpiston 35 is arranged for operation in chamber13 andconnecting saidpiston with a crank 360111 shaft 28 is a connecting rod 37.

Arranged to the sides of crank 36 and dia-' metrically opposite theretoare cranks 38 that are; connected by connecting rods 39 to pistons 40that arev arranged for o eration within combustion chambers 17 an 18.

The cranks 3 6 and. 38 for the power unit controlling the, cylinders 13,17 and 18 are 'arr anged120 in advance in the direction of crankrotation from cranks 31 and 32 that are. associated with the power unitcomprising the cylinders12, 15 and 16. A crank 41 beneath the chambers19 and 20, said cranks 44 being disposed diametrically opposite to crank41.

Pistons 45 are arranged for operation within combustion chambers 19 and20, said pistons being connected to the cranks 44 by connecting rods 46.The cranks 41 and 44 are disposed 120 in advance in the direction ofcrank rotation of cranks 36 and 38, and 240 inadvance in the directionof crank rotation of cranks 31 and 32. Thus the three sets of cranks forthe three power units of the engine are disposed 120 apart, saidarrangement tending to eliminate centrifugal couple and producinguniform torque and an even flow of power in the crank shaft.

These last mentioned advantageous results are enhanced by thearrangement of suitable counterba'ancing weights 47 that may be formedintegral with or fixed to the arms that are arranged to the sides ofcranks 31, 36 and 41.

Formed through the side wall of cylinder block 10 and communicatingwiththe intermediate portions of the pumping chambers 12, 13 and 14'aregaseous fuel inlet ports 48 that receive gaseous fuel from a suitablesource of supply, such as a carbureter. Formed throughthe side wall ofblock 21 and leading from the upper or inner ends of the pumpingchambers 12, 13 and 14 are compressed gaseous fuel outlet ports 49 thatcommunicate with the upper ends of inclined transfer ducts 50, (thelower ends of which latter communicate with fuel transfer inlet ports 51that are formed through the wall of cylinder block 10 and whichcommunicate, respectively, with the intermediate portions of combustionchambers 16, 18 and 20.

Formed through the wall of block 10 and leading from the intermediateportions of combustion chambers 15, 17 and 19 are e2:- haust ports, suchas 52, and if desired these ports may all communicate with a suitablyarranged exhaust manifold.

All 'of the ports 48, 51 and 52 occupy practically the same plane, andsaid ports are wholly uncovered and open only when the respectivepistons are at the lower or outer ends of their travel.

Inasmuch as each pumping'piston moves (simultaneously with and inopposition to the reciprocatingmovement of the combustion pistons withwhich it is associated, each pumping piston will be at the lower orouter end of its travel when the associated combustion pistons are atthe upper or inner ends of their travel and whenso positioned thegaseeeaeor ous fuelinlet ports into the pumping chamher will be fullyuncovered and open so as to admit a charge of gaseous fuel from thesource of supply. As the pumping piston moves upward or inward, .thegaseous fuel inlet ports are closed and during the succeeding upward orinward travel of said piston, the gaseous fuel within said pumpmgchamber will be compressed in the upper portion thereof, and in thetransfer duct that leads from the outlet transfer port at the upper endof said pumping chamber. As the pumping piston approaches high center,the combustion pistons associated therewith or within the adjacentcombustion chambers approach and pass their low centers, therebysimultaneously uncovering the exhaust ports and the precompressedgaseous fuel inlet ports, and the precomprcssed charge of gaseous fuelentering the uncovered inlet ports rushes upwardly through thecombustion chamber into which said ports open, and said gaseous fuelpasses from thence through the common clearance chamber that connectsthe head portions of the combustion chambers, and said gaseous fuel thenpasses downwardly through the combustion chamber having the exhaustports, with the result that the products of combustion of the previouslyignited charge are expelled through said exhaust ports.

On the succeeding upward or inner strokes of the pistons within thecombustion chambers, the precompressed gaseous fuel charge drawn intosaid chambers will be compressed in the common clearance chamber thatconnects the head portions of said combustion chambers, and as saidcombustion chambers pass their high centers this compressed charge ofgaseous fuel will be ignited by a spark produced between the terminalsof the electrodes of .the corresponding spark plug. Obviously theexpansion following combus tion of this compressed gaseous fuel chargewill act upon the pistons in the usual manner to drive the same downwardor outward upon their power stroke. I

By providing an engine having three power units, each unit comprising apair of connected combustion cylinders and a gaseous fuel pumpingcylinder, and arranging the cranks to which the pistons of the threeunits .are connected 120 apart the crank shaft of the engine is drivenso as to produce with minimum, vibration a relatively high degree ofpower, and this smooth running efiect is enhanced by reason of the factthat the crank armsto the sides of the cranks to which the pistons inthe pumping chambers are connected are provided with counter-balancingweights.

The symmetrical arrangement of the cylinders forming the power units inmy im- 1 proved arrangement, and likewise thesymmetrical arrangement ofthe connectlons beefiective in equalizin tween the pistons and the crankshaft, is

the stresses and torque impressed on sald crank shaft by the powerpistons, and likewise the strains impressed on said crank shaft by theresistance offered to the pumping pistons during the precompression ofthe gaseous fuel charges.

It will'be understood that various minor changes in the size, form andconstruction of my improved two stroke cycle internal combustion enginemay be made without departing from the spirit of my invention, the scopeof which is set forth in the appended claims. v

I claim as my invention:

1. In a two stroke cycle internal combustion engine, a series of ninecylinders arranged in row, the entire series of. cylinders beingarranged to form three power units, each comprising a pair of combustioncylinders and a single gaseous fuel pumping cylinder, said pumpingcylinder being arranged between the pair of combustion cylinders of theunit with which it is associated, the members of the pair of combustioncylinders of each unit being connected at their head ends by a commonclearance chamber, the pumping cylinder of each unit being provided witha gaseous fuel inlet port and with a pumped gaseous fuel outlet port, aduct leading from said outlet port to the intermediate portion of one ofthe adjacent combustion cylinders, the other combustion cylinder of thesame unit being provided with an exhaust port, pistons each comprising apair of combustion cylinders and a single gaseous fuel pumping cylinder,said pumping cylinder being arranged between the pair of combustioncylinders of the unit with which it is associated,\th'e members of thepair of combustion cylinders of each unit belng connected at their headends by a common clearance chamber, the

pumping cylinder of each unit being provided with a gaseous fuel inletport and with a pumped gaseous fuel outlet port, a duct leading fromsaid outlet port to the intermediate portion of one of the adjacentcombustion cylinders, the other combustion cylinder of the same unitbeing provided with an exhaust port, pistons arranged for operationwithin the three cylinders of each unit, a crank shaft having nineseparate throws to which all of the pistons are separately andrespectively connected, and the corresponding members of the three setsof cranks being arranged 120 apart.

t In testimony whereof I afiix my signa- EVERETT R. BURTNETT.

